Brush Bot Races

Problem Scenario

Ever bought a toy that you played with all the time. Until your mom steps on it, or your dog eats it. Well the crazy of "hex bugs" may have your invaded in to your house by a younger sibling and we all know when they break their brand new toy it your fault. But what if you were able to stop them from tears, by making them a new one that can go where ever they want. If you knew how to manipulate the bristles on the bottom of a home made "hex bug" you could make a toy that wood go in circles, straight lines, and waved lines.

Broad Question

How do brush bugs operate?

Specific Question

Can you manipulate the brushes on a brush bug to follow a path you chose. And predict its path.

Hypothesis

I believe I will be able to predict the paths they will follow and how much variation there is depending on the brushes.

Graph of Hypothesis

Graph Of Hypothesis

Variables

Independent Variable:

Short Bristles
Long Bristles
Titled out bristles
Tilted in bristles

Dependent Variable:

Variation off the line on how much they stay on track.

Variables That Need To Be Controlled:

Manipulation of bristles
Same vibration/ motor.

Vocabulary List That Needs Explanation

Brush Bot
Prediction
On Track
Percent
Cell phone vibration mechanism

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General Plan

In my experiment I will be testing how brush bot move and operate. After having a fair conclusion and idea on how the small robot works i then will be taking four different poisons of the bristles (Long,Short,Tilted Outward, Folded Inward) and test to see which one of them stays in the straightest line. I will test this by setting the "bug" on a piece of paper with a hundred centimeter line drawn on it. Then I will turn the brush bot on and follow its path with a pencil recording everything it does. After the bot has reached the end of the paper I will take a centimeter ruler and measure how many centimeter the bot differs from the line. This number will be subtracted from 100. The difference is the percent. This will be averaged together with three other differences from different trials of the same brush setting.

Potential Problems And Solutions

The potential problem I face is that the bush bots will not travel along the line at all and the data will be inconclusive.

They way I will fix this is trial and error, in the event of this happening I will have to continue the move the the bristles until I find a certain set of manipulations that will sacrifice the needs of what the test requires. If I decide that it is impossible to move the bristles to make the bot to go in a straight I will have to conduct an experiment on why the bristles do not effect the bots paths and maneuverability.

Safety Or Environmental Concerns

While doing my experiment I must solder wires together. In this process I use a very hot tool, called a soldering iron, this is placed in one hand while a metal rod, the solder, is in the other hand. bringing the two together a drop of hot metal will drop onto the spot where the two wires meet. This metal cools almost instantly and hold a strong bond, connecting the two wires to form one.
This is a safety concern due to the fact I am using a extremism hot metal tool which I could burn myself with.
I will avoid this by handling the tools with great care and being aware of my surroundings at all times. I will also be using the soldering iron on a table that i can set the hot tool on without the risk of catching it on fire.

Experimental Design

I will take one of the toothbrush heads and Velcro the battery mechanism to it. Then I will set it on a piece of paper with a line on it. I will measure the percentage of how much it stays or differences from the line I will use this percent to find which one of the different toothbrush heads is the most accurate to go in a straight line. I will measure the percent by placing the bot on a piece of paper with a hundred centimeter straight line on it . Then I will turn the brush bot on and follow its path with a pencil recording everything it does. After the bot has reached the end of the paper I will take a centimeter ruler and measure how many centimeter the bot differs from the line. This number will be subtracted from 100. The difference is the percent. This will be averaged together with three other differences from different trials of the same brush setting.

Resources and Budget Table

Item	Number needed	Where I will get this	Cost
cell phone vibration	1	out of an old junk cell phone	$0
Velcro	4 sets	around the house	$0
watch battery	1	Walmart	$8
paper with line	1	make	$0
Toothbrushes	4	dollar tree	$4
Switch	1	lows	$5

Detailed Procedure

1. First I will Velcro the vibrator mechanism to the out ward tilted toothbrush head.
2. Then I will place it on the paper with a measuring line.
3. After I will turn it on and measure by drawing where it goes and seeing how much it differences from the line.
4.after i will repeat steps 1-3 with each of the different toothbrush heads.
5. I will test each brush three times
6. I will measure the percent by placing the bots on a 100 cm line.
7. then i will turn the bot on, while following the bot with a pencil and drawing its path behind it.
8. After the bot makes it to the end of line i will take a ruler and measure how many centimeters of the path is off the line.
9. Then having that measure meant i will be able to convert this in to a percent.
10. then average all the different trials together and get my final number.

Diagram

Photo List

Picture of bugs
Piture of experement
Picture of building them

Time Line

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Data Table

Tilted out	Tilted In	Long	Short
64%	34%	53%	81%
71%	12%	47%	73%
68%	42%	64%	79%

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Data Analysis

All Raw Data

Graphs

Photos

Results

In this experiment I found that the short bristle brushes have the most accurate bot. On average the short bristle bot was accurate 73 percent of the time, this means that this bot differs from the line 23 percent of the time. The other brushes long, tilted out, and tilted in have the average accuracy of 52%, 68%, and 29% . This shows that this bot shows a lot bigger rate in accuracy, then all the others.

Conclusion

I reject my hypothesis, as I had stated that the most accurate bot would be the tilted outward brush not the short bristle. In the end of this experiment I found that the short bristled brush bot is the best and most accurate bot out of this experiment. This bot is the most accurate and abides by both my theories This bot preformed the best and had the most cohesive data out of the four bots. All three trials where positive which gives the bot the best average.

Discussion

Through this experiment I have discovered that the short bristle was the best tooth brush head to have it travel in a straight line. This brush bot was accurate 78 percent of the time. This brush bots average is much higher than the others. I believe this is because the shorter bristles give the vibrations less places to go, where the long bristles send vibrations in all directions. When the mechanism on top of the bristle send vibrations down each strand of the tooth brush head the vibrations are sent into the surface where it is moving and lift the bot up and down off the surface very rapidly which causes the bot to move around randomly. My theory is that the less strands the vibrations are able to go down the less the can bounce off each other and the straighter it will travel. I also believe that balance has a key element in the way these bots move. This element is proven by the data of the inward titled bot. This bot had the worst average of staying on the line, and I believe that this is because of how long the length is and how unbalanced it is. The length of this brush is just as long as the tilted outward brush and only slightly smaller than the long bristle brush.Because the bristles are tilted into each other this gives the bot lees bottom surface area giving it less balance My first theory of how the vibrations are bouncing off each other more, when the bristles are longer is proven by the data of the long bristle bot, and my second theory of balance is proven by how good the scores are for the tilted out ward bot with the most surface area. So why didn't the titled out ward bristles win? Might ask because the rules of my first theory says the longer the brushes the worst it would do. Each head either has one of the other of the two theories. The long bristle brush has the some surface area and balance but too much length the tilted inward bristles have an OK length but has no surface area, the short bristle brush has some surface area and a very short length which is good. If we were to conduct further experiments with this question I would think a short bristled , tilted outward brush would be the best combination of length and balance it a brush bot. If I were to test this I believe that the accuracy would be in the upwards of 90 percent or higher with this brush.

Benefit to Community and/or Science

This experiment is beneficial in the industry of toys and small house hold robots. Through out this experiment I learned how and in which was bristles on a brush bot could be manipulated to follow a path you chose. Through further research I believe that this experiment could greatly improve manufacturing and design of these toys. for instance they could improve the design of these bots by giving the interchangeable heads for different paths. Considering how much that the market in small robotic toys have been replaced with newer technology and gaming devices this could be exactly what the market needs to pick there profits back up.

Background Research

References

Abstract

The experiment I tested was "How do brush bugs operate?" I tested this question by making a small motor which vibrated. I then attached this to four different types of tooth brush heads. (Short Bristled, Long Bristle, Tilted Outward Bristles, and Tilted Inward Bristles.) I then place one of the bots on a hundred centimeter line, turned on the bot and then followed the path carefully with a pencil drawing it's path as it was made. After the bot reached the end of line I measured how many centimeters the path differed from the line. I then took that number and subtracted it from one hundred, and came up with the percent. I did this repeated this three times for each bot. Then averaged all the percents together to come up with one final data piece.